Facebook Pixel

Cold Sores Symptoms & Diagnosis


The first episode of herpes simplex 1 infection may result in 3-14 days of:

  • Swollen, sore throat
  • Mouth sores
  • Fever
  • Decreased energy
  • Aches and pains
  • Difficulty eating
  • Swollen glands in the neck
  • Headache

In the day just prior to the virus reappearing as a cold sore, you may notice some itching, burning, or pain in the area where the cold sore will appear.

Symptoms of cold sores on the lips, mouth, or skin include:

  • Small, painful, fluid-filled, red-rimmed blisters
  • Pain, tingling, or itching for a day or two before the blister appears
  • After a few days, drying of the blister, which then forms a yellow crust and shallow ulcers


The doctor will ask about your symptoms and medical history, and examine the blisters. Usually, the doctor can easily diagnose a cold sore by looking at it. Cold sores have a relatively classic appearance. In rare cases, the doctor may need to take a piece of a blister to analyze it or take a blood sample for testing.

Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition. Copyright © 2023 EBSCO Publishing All rights reserved.

The Latest in Cold Sores Symptoms & Diagnosis

ASK Your Health Question

It's FREE and you'll get a response within 24 hours


POST Info, Tips & Stories

Inspire others to learn from your experiences. Tell your story!

Get Email Updates

Cold Sores Guide

Have a question? We're here to help. Ask the Community.


Health Newsletter

Receive the latest and greatest in women's health and wellness from EmpowHER - for free!